Pallister–Killian syndrome in the practice of a pediatrician and a neurologist

Pallister–Killian syndrome (tetrasomy 12p, mosaic isochromosome 12p syndrome) (OMIM#601803) is a rare genetic disease characterized by multiple developmental abnormalities and mental retardation. The frequency of occurrence is 5.1:1,000,000. Newborns with this syndrome are characterized by muscular hypotension, which causes children to experience breathing difficulty and feeding problems, craniofacial dysmorphic disorder: a “rough” face — a high protruding forehead, oblique eye slits with epicanthus, hypertelorism, a wide and flattened nose with turned-out nostrils, low-set and dysplastic ears, micrognathia, a wide mouth with an inverted lower lip, a thin upper lip in the shape of a Cupid’s bow. Most children have a high hairline, bilateral frontal-temporal alopecia, sparse eyebrows or eyelashes, and areas of hypopigmentation in the form of light spots or streaks. The neurological status most often shows a serious delay in the pace of speech, motor, and intellectual development, although a more “mild” course of the disease is described. Specific speech disorders are also characteristic.

To verify the diagnosis, the child needs to examine the buccal epithelium or fibroblasts using FISH analysis. The prognosis of the disease is unfavourable. It is also aggravated by the presence of profound intellectual disability and the possible development of seizures. Currently, no specific treatment for patients has been developed. Depending on the clinical manifestations, therapy may include surgical correction of the identified congenital disorders. One of the important stages of managing patients with such a diagnosis is working with psychologists and educators to support the intellectual development and socialization of the child.

The article presents a clinical case of managing a child with Pallister–Killian syndrome, as well as current views on the diagnosis of this disease.

Contribution:
Kharitonova N.A. — concept and design of the study, collection and processing of material, writing the text, editing;
Basargina M.A. — editing;
Vavilova N.V. — collection and processing of material;
Uvakina Ye.V. — collection and processing of material;
Nesterovich M.I. — collection and processing of material.
All authors — responsibility for the integrity of all parts of the manuscript and approval of its final version.

Acknowledgment. The study had no sponsorship.

Conflict of interest. The authors declare no conflict of interest.

Received: January 20, 2025
Accepted: February 7, 2025
Published: August 20, 2025

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